Using the /enititydata command, attributes can be modified that affect an entity's speed, health, or strength. However, when I attempted to slow a ghast like this, there was no effect. Also, there is no noticeable difference when a slow potion is used against them.
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marcono1234
Sonicwave
Possibly related to MC-73983.
migrated
isn't this a duplicate of MC-40949, instead of relates to?
That is probably MC-33110 and maybe MC-44524